Access and Terminals (AT); Analogue access to the Public Switched Telephone Network (PSTN); Protocol over the local loop for display and related services; Terminal equipment requirements; Part 5: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT)
接入和终端(AT);公共交换电话网(PSTN)的模拟接入;用于显示和相关服务的本地环路协议;终端设备要求;第5部分:抽象测试套件(ATS)和部分协议执行额外测试信息(PIXIT)